Sprinkler with pressure regulation

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of prior application Ser. No. 12/710,871, filed Feb. 23, 2010, which is a continuation of prior application Ser. No. 11/175,609, filed Jul. 6, 2005, now U.S. Pat. No. 7,681,807 B2, which are hereby incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The invention relates to a pressure regulator for a sprinkler and, more particularly, to a pressure regulator located in the stem or moveable housing of a pop-up type sprinkler.

BACKGROUND OF THE INVENTION

Currently, pressure regulators are known in the art for use with sprinklers where the source water pressure may vary or otherwise be excessive for the sprinkler. Under ideal operating conditions, the internal pressure due to water flow would be relatively constant or at least within a specified, limited range. If the internal pressure exceeds the specified range, the sprinkler will not distribute water in a desirable manner. For instance, the water may be emitted at an excessive distance or force, and the desired coverage area will not be properly watered. Alternatively, a spinning-type sprinkler, having a head portion rotated by the force of the water flow, may spin too rapidly. In such a case, the emitted water stream or streams will not have time to develop the proper emission profile, instead “tailing” and being emitted a shorter distance than desired.

In simple terms, a pressure regulator is a mechanism having a portion or member that shifts positions depending on water pressure so that the water flow through the sprinkler remains within a desired range as the water pressure varies. A pressure regulator typically utilizes a pressure responsive moveable flow member that shifts within the water flow to regulate the size of a passageway around or through the moveable member and a stationary structure such as a pressure regulator valve seat. If the water pressure is excessive, the moveable member is shifted against the spring bias towards the structure so that the passage between the moveable member and the stationary structure is decreased in size. At ideal pressure, or below, the moveable member is biased by the spring away from the structure so as to maximize the size of the passage therebetween and to minimize the pressure drop across the interface between the moveable member and the valve seat.

In many cases, the moveable member is biased open and away from the valve seat. In some applications, the moveable member is biased towards the outlet or nozzle of the sprinkler and has a first face, downwardly directed into an incoming water stream, and a second face upwardly directed towards a cavity into which the water flows. As the water fills the cavity under pressure, the water exerts a pressure against both the first and second faces. By providing a larger surface area on the upwardly-facing second face than on the downwardly facing first face, the pressure acting downwardly on the moveable member is greater than the force acting upwardly. If there is a sufficient force differential between the faces, the spring bias is overcome and the moveable member is forced downward and towards the valve seat. The pressure regulator thereby acts to decrease the passageway between the moveable member and valve seat for the water, which consequently decreases the water flow and increases the pressure drop therethrough.

These types of pressure regulators are located in the flow of the water. As the water flows through the source pipe and through each component of the sprinkler itself, such as the inlet or pipe junctures, there is a pressure or head loss. If not located in close proximity to the sprinkler, the pressure regulator is subject to pressures which are not the same as those that would be experienced by the sprinkler head itself. It is therefore desirable for the pressure regulator to be closely located to the components of the sprinkler whose operation is effected by the water pressure.

A pop-up type sprinkler includes a case housing that connects to a source pipe for delivering water to the sprinkler. Within the case housing, a moving or moveable housing is located. The moveable housing is spring-biased to a retracted position so that it is located within the case when the sprinkler is not operating. When the sprinkler is activated, water is delivered to the sprinkler so that a water stream applies pressure to the moveable housing, thereby overcoming the spring bias and forcing the housing upward to a position extended from the case. The water continues through the moveable housing and is emitted by a sprinkler nozzle or outlet.

The pop-up sprinkler has a size which is dependent on the application and often includes a mechanism for allowing a sprinkler head portion of the moveable housing to rotate. For instance, a spinning-type sprinkler has a spinning deflector plate located above openings in the moveable housing through which water passes. The water strikes vanes of the deflector plate to cause the water to be distributed radially therefrom and to drive the deflector plate in a rotational manner. This type of sprinkler has a relatively small head portion.

In other cases, the moveable housing includes a drive train for converting the kinetic energy and force into rotational torque for controllably rotating the head portion of the moveable housing. The water is then emitted from the rotating head portion. Although some sprinklers have a speed control mechanism, in many types of sprinklers it is the pressure and flow rate of the water stream that are responsible for the rotation rate of the head portion. In use, control of the water flow through the drive train by a pressure regulator benefits from the pressure regulator being positioned upstream from the drive train.

Use of a conventional pressure regulator with a drive train can significantly increases the size, and in particular the length, of the moveable housing. The larger moveable housing may also requires a larger stem housing into which the moveable housing may retract. These factors contribute to an increase in cost and installation requirements.

In other applications, the pressure regulator may be located in the source pipe or upstream from a sprinkler head of any type. As described, the pressure regulator design utilizes a spring, which often requires a cavity within which the spring is located. This design benefits from the cavity being generally sealed from the pressurized water flow. If pressurized water is allowed to enter, the described pressure-differential is reduced or eliminated. However, the shifting of the moveable member causes the size of the cavity to be compressed and expanded. Therefore, the cavity is preferably vented to an ambient or reference pressure, such as the atmospheric environment.

Providing a vent can be problematic because the vent often provides a path for dirt and grit to enter the atmospheric or referential pressure cavity. Such entry may cause problems with the shifting of the moveable member, the moving of the spring, and the sealing between the moveable member and a support structure.

Accordingly, there has been a need for an improved pressure regulator, and a pressure regulator for use in compact constructions.

BRIEF DESCRIPTION OF THE DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> is a cross-sectional view of a sprinkler including a moveable housing having a pressure regulator and a drive mechanism for rotating a head portion located on the moveable housing;

<figref idref="DRAWINGS">FIG. 2</figref> is a cross-sectional fragmentary view of the sprinkler of <figref idref="DRAWINGS">FIG. 1</figref> showing the moveable housing and showing the pressure regulator in a fully open position;

<figref idref="DRAWINGS">FIG. 3</figref> is a cross-sectional fragmentary view of the sprinkler of <figref idref="DRAWINGS">FIG. 1</figref> showing the pressure regulator in an fully closed position;

<figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of a body of the pressure regulator showing a body cup and a body shell;

<figref idref="DRAWINGS">FIG. 5</figref> is a cross-sectional view of the body of the pressure regulator of <figref idref="DRAWINGS">FIG. 1</figref> showing an atmospheric vent positioned between two seals;

<figref idref="DRAWINGS">FIG. 6</figref> is a bottom view of the body of the pressure regulator of <figref idref="DRAWINGS">FIG. 1</figref> showing passageways separated by ribs for water flow entering the pressure regulator;

<figref idref="DRAWINGS">FIG. 7</figref> is a top view of the body showing portions of a bearing assembly within the body cup;

<figref idref="DRAWINGS">FIG. 8</figref> is a cross-sectional view of a swirl stator for directing water streams into the drive mechanism and a bypass assembly in a closed position;

<figref idref="DRAWINGS">FIG. 9</figref> is a cross-sectional view of the swirl stator of <figref idref="DRAWINGS">FIG. 8</figref> showing the bypass assembly in an open position;

<figref idref="DRAWINGS">FIG. 10</figref> is a perspective view of the swirl stator from the top;

<figref idref="DRAWINGS">FIG. 11</figref> is a perspective view of the swirl stator from the bottom;

<figref idref="DRAWINGS">FIG. 12</figref> is a perspective view of a retention member of the bypass assembly;

<figref idref="DRAWINGS">FIG. 13</figref> is a side elevational view of a moveable member of the pressure regulator;

<figref idref="DRAWINGS">FIG. 14</figref> is a cross-sectional view of the moveable member of <figref idref="DRAWINGS">FIG. 13</figref> showing a cup-shaped interior cavity for receiving the bypass assembly therein;

<figref idref="DRAWINGS">FIG. 15</figref> is a perspective view of a retention mechanism of the sprinkler.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring initially to <figref idref="DRAWINGS">FIGS. 1 and 2</figref>, a compact design for a sprinkler <b>10</b> is depicted having a pressure regulator module or “PR” module <b>20</b> located within a moveable housing or riser <b>30</b>. The sprinkler <b>10</b> is connected to a source pipe (not shown) for receiving a flow of water within the sprinkler <b>10</b>. The sprinkler <b>10</b>, as depicted, is a pop-up type sprinkler having a case <b>34</b> connected to the source pipe, and the riser <b>30</b> is allowed to reciprocate within the case <b>34</b>. The riser <b>30</b> is biased downward into the case <b>34</b> to a telescopically retracted position on the case <b>34</b> by a retract spring <b>36</b> located around an exterior surface <b>38</b> of the riser <b>30</b>. A spring bottom portion <b>40</b> contacts a shoulder <b>42</b> located proximate a lower portion <b>44</b> of the riser <b>30</b>, while a top portion <b>46</b> of the spring <b>36</b> contacts a generally stationary shoulder <b>48</b> contained inside the case <b>34</b>. Above the shoulder <b>48</b> is an annular wiper seal <b>50</b> secured within the case <b>34</b> and slidingly abutting in a sealing fashion the exterior surface <b>38</b> of the riser <b>30</b> so that water does not flow between the exterior surface <b>38</b> of the riser <b>30</b> and an interior surface <b>54</b> of the case <b>34</b>. When the water source is turned on and the sprinkler <b>10</b> is activated, the pressure from the flow of water overcomes the force of the spring <b>36</b> to force the riser <b>30</b> from the retracted position to a telescopically extended position. In doing so, a nozzle <b>52</b> is exposed so that water may be emitted therefrom. The riser <b>30</b> is depicted in <figref idref="DRAWINGS">FIG. 1</figref> in the extended position.

As shown, the riser <b>30</b> includes a sprinkler head <b>60</b> rotated around a central axis X by a drive mechanism <b>70</b>. As the water flows through the sprinkler <b>10</b>, the force of the water imparts energy for powering the drive mechanism <b>70</b>. The sprinkler head <b>60</b> has a rotational friction that requires a torque to rotate, and the sprinkler head <b>60</b> has a preferred rotational speed. The drive mechanism <b>70</b> converts the energy from the water to rotational movement to achieve the preferred rotational speed and to create the requisite torque.

The drive mechanism <b>70</b> includes a turbine <b>72</b> located in an intermediate passageway <b>74</b> and an axle <b>76</b> which the turbine <b>72</b> rotates. The turbine <b>72</b> includes structure, such as vanes <b>78</b>, that the water flowing through the intermediate passageway <b>74</b> impacts, thereby causing the turbine <b>72</b> to rotate. Above the turbine <b>72</b>, a first gear <b>80</b> is connected to the axle <b>76</b> so that the turbine <b>72</b> and first gear <b>80</b> rotate together (see <figref idref="DRAWINGS">FIG. 1</figref>). The first gear <b>80</b> communicates with a drive train <b>82</b> having a gear reduction ratio to reduce the relatively high rotational velocity of the turbine <b>72</b> and first gear <b>80</b> to a lower velocity with increased torque. The drive train <b>82</b> transmits the high-torque, low-velocity motion to the head <b>60</b>, thereby causing the head <b>60</b> to rotate about the axis X. The water, after passing through the turbine <b>72</b>, flows through an upper flow passageway <b>90</b>, generally located to one side of the drive train <b>82</b>, and into the head <b>60</b> for emission by the rotating nozzle <b>52</b> in a radial pattern.

The sprinkler <b>10</b> includes a regulator valve assembly <b>180</b> and a bypass valve assembly <b>350</b> for controlling the path, pressure, and quantity of water flow through the sprinkler <b>10</b>. Initially, the water enters the sprinkler <b>10</b> at an inlet <b>94</b> formed in a lower end of the case <b>34</b> and in communication with the source pipe. The inlet <b>94</b> communicates with a cavity <b>96</b> defined by the case <b>34</b> and by the bottom of the riser <b>30</b>. The water then flows through a filter screen <b>98</b> in a lower portion of the riser <b>30</b>. The filter screen <b>98</b> may be structured so as to receive a portion of the PR module <b>20</b> to reduce the axial space required for the sprinkler <b>10</b>.

With reference to <figref idref="DRAWINGS">FIGS. 4-7</figref>, the PR module <b>20</b> has a body <b>122</b> that generally seals with an interior surface <b>39</b> (<figref idref="DRAWINGS">FIG. 2</figref>) of the riser <b>30</b> with upper and lower seals <b>110</b>, <b>112</b> in the form of O-rings. The body <b>122</b> has a lower cylindrical cup <b>124</b> and an upper cylinder <b>126</b> interconnected by radially extending support ribs <b>128</b>. The body <b>122</b> is, when installed, concentrically positioned along the axis X (<figref idref="DRAWINGS">FIG. 1</figref>) of the sprinkler <b>10</b>. Each rib <b>128</b> has a lower elongated portion <b>128</b><i>a </i>that extends vertically along an exterior <b>130</b> of the cup <b>124</b> that is tapered radially outwardly from bottom to top, and the screen filter <b>98</b> is positioned generally around the cup <b>124</b>. Each rib <b>128</b> also includes an upper radial portion <b>128</b><i>b </i>that includes a downwardly facing shoulder <b>132</b> a short distance below a junction <b>134</b> (<figref idref="DRAWINGS">FIG. 7</figref>) between the upper portion <b>128</b><i>b </i>of the rib <b>128</b> and the shell <b>126</b>. The shoulder <b>132</b> defines the upper position of the screen <b>98</b> when the screen <b>98</b> is extended over the cup <b>124</b>.

In addition, the shoulder <b>132</b> allows a gap <b>138</b> between a lower edge <b>140</b> of the shell <b>126</b> and a top portion <b>142</b> of the screen <b>98</b> (see <figref idref="DRAWINGS">FIGS. 2 and 5</figref>). The ribs <b>128</b> further form radially outwardly facing shoulders <b>150</b> spaced a distance from the riser interior surface <b>39</b>. A retention mechanism <b>152</b> is secured in the gap <b>138</b> and between the shoulders <b>150</b> and the interior surface <b>39</b> for generally preventing the PR module <b>20</b> from shifting within the riser <b>30</b>.

Preferably, the retention mechanism <b>152</b> is a washer-like member formed of metal having a central annular ring <b>154</b> surrounded by teeth <b>156</b> that radially extend and are inclined downward, as can be seen in <figref idref="DRAWINGS">FIG. 15</figref>. An inner edge <b>155</b> of the ring <b>154</b> is positioned with a small clearance around the shoulders <b>150</b>, and the teeth <b>156</b> frictionally engage the interior surface <b>39</b>. It should be noted that the retention mechanism may be provided as a generally planar component such that the teeth <b>156</b> extend radially from the ring <b>154</b> without an inclination.

During installation, the described incline may be imparted to the teeth <b>156</b> such that the teeth <b>156</b> resist moving downward within the riser <b>30</b>. In this manner, the PR module <b>20</b> and retention mechanism <b>152</b> are easily installed from the bottom of the riser <b>30</b>, while resisting forces that may otherwise force the PR module <b>20</b> to shift downwardly within the riser <b>30</b>.

The retention mechanism <b>152</b> is positioned to reduce stress concentrations between itself and the riser <b>30</b>. As can be seen in <figref idref="DRAWINGS">FIG. 2</figref>, the retention mechanism <b>152</b> is in contact with the interior surface <b>39</b> at a position below a pressure activated lip <b>50</b><i>a </i>of the wiper seal <b>50</b>. At this position, the interior surface <b>39</b> and the exterior surface <b>38</b> of the riser <b>30</b> are at equal pressure, generally line pressure from the water input. Though the teeth <b>156</b> of the retention mechanism <b>152</b> may gouge the interior surface <b>39</b>, the balance of pressure on each side of the riser <b>30</b> in this region reduces the likelihood that stress concentrations will result.

The water flows through the screen <b>98</b>, around the cup <b>124</b>, and into the PR module <b>20</b>. More specifically, the upper portion <b>128</b><i>b </i>ribs <b>128</b> define openings <b>160</b> in the body <b>122</b>, best seen in <figref idref="DRAWINGS">FIGS. 6 and 7</figref>. As the body <b>122</b> is sealed with the riser <b>30</b> by the seals <b>110</b>, <b>112</b>, the water does not flow around the PR module, instead being directed into the PR module <b>20</b>. The interior of the PR module defines a lower passageway <b>162</b> (<figref idref="DRAWINGS">FIG. 2</figref>), with water entering the lower passageway <b>162</b> at the openings <b>160</b>. The water exits the lower passageway <b>162</b> through a swirl stator <b>170</b> (<figref idref="DRAWINGS">FIG. 2</figref>) having an outer annular shell <b>172</b> and a central plate portion <b>174</b> (<figref idref="DRAWINGS">FIG. 10</figref>), features that will be discussed below.

The PR module <b>20</b> includes the pressure regulating valve assembly <b>180</b> and the bypass valve assembly <b>350</b> for regulating the pressure and flow rate of water through the sprinkler <b>10</b>. Each valve assembly <b>180</b>, <b>350</b> has, in various forms, an upper head portion and a lower stem portion supporting the head portion. As can be seen in <figref idref="DRAWINGS">FIG. 3</figref>, the pressure regulating valve assembly <b>180</b> includes a stationary annular valve seat member <b>182</b> and a pressure responsive moveable member <b>200</b>. The valve seat member <b>182</b> includes a generally annular stepped outer ring <b>186</b> having an upper section <b>188</b> and a lower section <b>190</b> with a greater diameter than the upper section <b>188</b> so as to form a shoulder <b>192</b> thereon. In assembly, the upper section <b>188</b> is received within the swirl stator shell <b>172</b>, the lower section <b>190</b> has a diameter substantially equal to that of the exterior of the stator shell <b>172</b>, and the shoulder <b>192</b> of the valve seat member <b>182</b> abuts a bottom surface <b>176</b> of the stator shell <b>172</b>. Furthermore, the upper section <b>188</b> has a top surface <b>189</b> that abuts a shoulder <b>178</b> formed on the interior of the swirl stator plate portion <b>174</b>. The diameters of the stator shell <b>172</b> and the lower section <b>190</b> are such that the stator shell <b>172</b> and lower section <b>190</b> are closely fitted within the body shell <b>126</b>.

Extending radially inwardly from the valve seat member ring <b>186</b> is a seat portion <b>198</b> having an upper surface forming a valve surface <b>194</b> and a lower surface <b>196</b>. The valve surface <b>194</b> arcs downwardly and towards the axis X, while the lower surface <b>196</b> arcs upwardly towards the axis X. In this manner, water flowing through the lower flow passageway <b>162</b> has a smooth, contoured path to minimize head loss.

The pressure regulating valve assembly <b>180</b> defines fully open and nearly closed positions for the PR module <b>20</b>, respectively depicted in <figref idref="DRAWINGS">FIGS. 2 and 3</figref>. The fully open position represents a condition where the water pressure in the PR module <b>20</b> is sufficiently lower than a pre-determined pressure regulation value such that the moveable member <b>200</b> does not shift from its upwardly biased position, as shown in <figref idref="DRAWINGS">FIG. 2</figref>. The nearly closed position represents a condition where the water pressure into the PR module <b>20</b> is very high, the nozzle <b>52</b> has a small opening, or both. It should be noted that the PR module <b>20</b> does not fully close under normal operation. The PR module <b>20</b> is effectively moved towards a closed position by water flowing therethrough. Were the flow entirely cut-off, as would be the case with a fully-closed PR module <b>20</b>, the water would not be flowing through such that the PR module <b>20</b> would immediately return to an open position.

The pressure regulating valve assembly <b>180</b> includes the pressure responsive moveable member <b>200</b> and a spring <b>202</b> biasing the moveable member <b>200</b> upward. In the fully open position, illustrated in <figref idref="DRAWINGS">FIG. 2</figref>, the moveable member <b>200</b> is spaced from the valve surface <b>194</b> so that the lower passageway <b>162</b> is open and water may pass therethrough, and the effect on the water flow through the passageway <b>162</b> is minimized. In contrast, the pressure regulating valve assembly <b>180</b> may be nearly closed by the moveable member <b>200</b> shifting downward against the spring <b>202</b> so that an upper flange <b>234</b>, discussed below, is positioned in close proximity to the valve surface <b>194</b>, as is illustrated in <figref idref="DRAWINGS">FIG. 3</figref>.

As can be seen in <figref idref="DRAWINGS">FIGS. 2</figref>, <b>3</b>, <b>13</b> and <b>14</b>, the moveable member <b>200</b> has a stepped exterior configuration that is first defined by a lower cylindrical bearing portion <b>204</b> and a frusto-conical section <b>206</b> tapering upwardly and outwardly. The lower end of the frusto-conical section has a diameter greater than that of the bearing portion <b>204</b> such that a shoulder <b>208</b> is formed therebetween. Above the frusto-conical section <b>206</b> is an intermediate cylindrical portion <b>210</b> having a diameter equal to the diameter of the upper end of the frusto-conical section <b>206</b>. The intermediate cylindrical portion <b>210</b> forms a shoulder <b>212</b> with an annular extension <b>214</b> of greater diameter than the intermediate cylindrical portion <b>210</b>. A groove <b>216</b> is defined by a top surface <b>218</b> of the annular extension <b>214</b> and a bottom shoulder <b>220</b> of a flow portion <b>222</b> formed at the upper portion of the moveable member <b>200</b>. The groove <b>216</b> receives a seal member <b>224</b> (<figref idref="DRAWINGS">FIGS. 2 and 14</figref>), as will be discussed below.

As can be seen, the flow portion <b>222</b> is defined by an arcuate flow surface <b>230</b> divided into quarters by vertically extending ribs <b>232</b> positioned preferably at 90 degree intervals around the circumference of the flow portion <b>222</b>. The arcuate surface <b>230</b> extends concavely inward toward the longitudinal axis of the moveable member <b>200</b>. The flow surface <b>230</b> curves away from the central axis X (<figref idref="DRAWINGS">FIG. 1</figref>), increasing from a smallest middle portion towards the bottom shoulder <b>220</b> and the upper flange <b>234</b>, and the upper flange <b>234</b> extends in the radial direction to a greater extent than does the bottom shoulder <b>220</b>. In the almost fully closed position, the upper flange <b>234</b> almost seats on the valve surface <b>194</b>, noted above. In the open position, and all positions between the open and almost closed positions, the valve surface <b>194</b>, the flow surface <b>230</b>, and the lower surface <b>196</b> of the valve seat member <b>182</b> define the lower passageway <b>162</b>, as can be seen in <figref idref="DRAWINGS">FIG. 2</figref>, for example. The distance between the upper flange <b>234</b> and the valve surface <b>194</b> determines the amount of water flow permitted through the pressure regulating valve assembly <b>180</b> and, hence, the amount of pressure drop therethrough.

As noted above, the moveable member <b>200</b> includes a bearing portion <b>204</b>, and the body <b>122</b> includes the cup <b>124</b> (see <figref idref="DRAWINGS">FIG. 5</figref>). The moveable member <b>200</b> and its associated spring <b>202</b> are received within the cup <b>124</b>. More specifically, a bottom edge <b>240</b> or coil of the spring <b>202</b> rests on an interior bottom surface <b>242</b> of the cup <b>124</b>, while a top edge <b>244</b> rests on the downwardly-facing shoulder <b>212</b> on the annular extension <b>214</b> so that the portions of the moveable member <b>200</b> below the annular extension <b>214</b> are received within the spring <b>202</b>. The spring <b>202</b> fits around the intermediate cylindrical portion <b>210</b>, and the frusto-conical portion <b>206</b> acts as a lead-in chamfer surface for installation of the spring <b>202</b> on the cylindrical portion <b>210</b>. In this manner, the frusto-conical portion <b>206</b> does not provide appreciable resistance to movement of the moveable member <b>200</b> relative to the spring <b>202</b>.

The spring <b>202</b> is sized so that, in the absence of any downward pressure on the moveable member <b>200</b>, the spring <b>202</b> extends out from the cup <b>124</b>. When assembled, the moveable member <b>200</b> and spring <b>202</b> are forced downward by, at the minimum, the swirl stator <b>170</b> contacting the upper flange <b>234</b>. At this minimum compression, the seal <b>224</b> is located within the cup <b>124</b> and contacts an inner surface <b>248</b> thereof. The seal <b>224</b> thus prevents water from flowing into a cup cavity <b>250</b> defined by the cup inner surface <b>248</b>, a moveable member outer surface <b>252</b> (<figref idref="DRAWINGS">FIG. 13</figref>), and the seal <b>224</b>.

With reference to <figref idref="DRAWINGS">FIGS. 2</figref>, <b>13</b>, and <b>14</b>, the seal <b>224</b> may be cup or V-shaped so as to have an inner annular portion <b>225</b> forming a base portion and an outer annular contact portion <b>226</b> extending upwardly and outwardly from a lower joint <b>227</b> therebetween. The lower joint <b>227</b> rests generally atop the annular extension top surface <b>218</b>. The inner portion <b>225</b> extends about the moveable member <b>200</b> between the top surface <b>218</b> and the moveable member flow portion bottom shoulder <b>220</b>. The outer portion <b>226</b> extends slightly outwardly from the moveable member <b>200</b> so as to form a resilient seal with the cup inner surface <b>248</b>. The outer portion <b>226</b> also extends slightly upwardly so that the movement of the seal <b>224</b> with respect to the cup inner surface <b>248</b> requires less force in the downward direction. That is, when the moveable member <b>200</b> is forced downward, the outer portion <b>226</b> may deflect inwardly so that the resistance between the seal <b>224</b> and the cup inner surface <b>248</b> is reduced. In contrast, when the moveable member <b>200</b> is forced upwardly by its spring <b>202</b>, the shaped of the outer portion <b>226</b> causes increased resistance to such a movement.

The seal <b>224</b> configuration provides a benefit in that fluid located within the cup cavity <b>250</b> may force itself out easier than other seal configurations. It is contemplated that water may force itself through the one or more of the seals described herein, such as the seal <b>224</b> or the wiper seal <b>50</b>, and settle within the cup cavity <b>250</b>. During sub-zero conditions, any water within the cup cavity <b>250</b> may freeze and expand. As the seal <b>224</b> is designed to deflect inwardly and pivot-like around the lower joint <b>227</b>, expanding water (ice) due to freezing can relatively easily force itself through the interface between the seal <b>224</b> and the cup inner surface <b>248</b>. It is believed, then, that this configuration may reduce damage to the PR module <b>20</b> in specific and the sprinkler <b>10</b> in general. Alternatively, an O-ring may be utilized as the seal <b>224</b>.

To suit its purpose, the moveable member <b>200</b> may move between the minimum compressed position, shown as the fully open position of <figref idref="DRAWINGS">FIG. 2</figref> where the upper flange <b>234</b> contacts the swirl stator <b>170</b> (as at <b>235</b>, <b>237</b>, <figref idref="DRAWINGS">FIG. 2</figref>), and a greater compressed position, such as that shown in <figref idref="DRAWINGS">FIG. 3</figref>. More broadly, the pressure regulation feature of the PR module <b>20</b> utilizes the shifting moveable member <b>200</b> to control the size of the lower passageway <b>162</b>. The moveable member <b>200</b> has a variety of surfaces in fluid or pressure communication with the lower passageway <b>162</b>, and it shifts in response to the pressure from the fluid flow being sufficiently greater than the spring bias to overcome the bias of spring <b>202</b>.

As best seen in <figref idref="DRAWINGS">FIG. 2</figref>, the pressure regulating valve assembly <b>180</b> includes a bearing assembly <b>280</b> formed between the body cup <b>124</b> and the moveable member <b>200</b>. With further reference to <figref idref="DRAWINGS">FIGS. 7 and 14</figref>, the cup <b>124</b> includes a central, axially aligned post <b>282</b> extending upward from the bottom surface <b>242</b> that is received in an axially aligned, vertical and cylindrical bearing cavity <b>284</b> formed in the moveable member <b>200</b> and extending through the bearing portion <b>204</b> and the frusto-conical section <b>206</b>. The post <b>282</b> is preferably vertically splined to reduce the contact area between a bearing surface <b>286</b> (<figref idref="DRAWINGS">FIG. 7</figref>) of the post <b>282</b> and an interior surface <b>283</b> (<figref idref="DRAWINGS">FIG. 14</figref>) of the bearing cavity <b>284</b>. For instance, the post <b>282</b> may have a cross-sectional profile of a five-pointed star, as illustrated in <figref idref="DRAWINGS">FIG. 7</figref>.

Surrounding and spaced a short distance from the moveable member <b>200</b> is a guide member <b>288</b> (<figref idref="DRAWINGS">FIGS. 2</figref>, <b>5</b>, <b>7</b>) which acts to align the spring <b>202</b>. The guide member <b>288</b> is generally an annular or cylindrical wall extending upwardly from the bottom surface <b>242</b> and, preferably, has either vertical slots <b>290</b> (<figref idref="DRAWINGS">FIG. 7</figref>) formed in the wall or comprises a series of cylindrical wall sections separated by a short gap. The moveable member <b>200</b> is able to reciprocate within the cup <b>124</b>, as described herein, and any fluid or debris that is able to enter the cup cavity <b>250</b> (<figref idref="DRAWINGS">FIG. 2</figref>) settles into the bottom of the cup <b>124</b>. The slots <b>290</b> or gaps allow any fluid or debris to be moved from the path of the moveable member <b>200</b> and help prevent particulate matter from becoming entrapped between the bearing surfaces of the post <b>282</b> and the moveable member bearing surface <b>283</b>. The guide member <b>288</b> further provides a defined path for the spring <b>202</b> to compress and decompress.

With reference to <figref idref="DRAWINGS">FIGS. 4-7</figref>, when the moveable member <b>200</b> shifts downwardly into the cup cavity <b>250</b>, the volume therein decreases. In order to avoid an increase in pressure in proportion to the volume decreases, the cup cavity <b>250</b> is in fluid communication with a cup vent in the form of a channel <b>260</b> (<figref idref="DRAWINGS">FIGS. 3</figref>, <b>5</b>). Referring to <figref idref="DRAWINGS">FIG. 6</figref>, one of the ribs <b>128</b> is a vent rib <b>128</b>′ with a larger dimension than the other ribs <b>128</b>. The vent rib <b>128</b>′ includes the cup vent channel <b>260</b>, formed as an internal passage within the rib <b>128</b>′, that allows the cup cavity <b>250</b> to communicate with a pressure sink, such as the atmospheric environment. Therefore, air in the cup cavity <b>250</b> can escape from, as well as enter into, the cup cavity <b>250</b> through the cup vent channel <b>260</b>.

The cup vent channel <b>260</b> has an opening <b>262</b> on an outside surface <b>127</b> of the body shell <b>126</b>. The vent opening <b>262</b> is surrounded by a series of walls <b>264</b> forming a rectangle and positioned between the upper and lower seals <b>110</b> and <b>112</b>. Each seal <b>110</b>, <b>112</b> is provided with a pair of annular ribs <b>114</b>, and each seal <b>110</b>, <b>112</b> itself is positioned between its respective rib pair. The seals <b>110</b>, <b>112</b> and their ribs <b>114</b> essentially define a space, referred to herein as the vent cavity <b>266</b> (<figref idref="DRAWINGS">FIG. 3</figref>), sealed from the internal pressure of the riser <b>30</b> and the sprinkler <b>10</b>, in general.

The differential between the pressure in the cavity <b>266</b> and within the riser <b>30</b> benefits the operation of the pressure regulating valve assembly <b>180</b> as a pressure regulator. In order for the pressure within the cup cavity <b>250</b> to remain at atmospheric pressure during operation with the riser <b>30</b> in the extended position, the vent cavity <b>266</b> communicates with a exit vent <b>270</b> formed in the riser <b>30</b> at a position so that the exit vent <b>270</b> is above the wiper seal <b>50</b> and communicates directly with the atmosphere.

The walls <b>264</b> are separated from the interior surface <b>39</b> of the riser <b>30</b> by a short distance, preferably in the order of 0.005 inches. In comparison, the exit vent <b>270</b> is approximately 0.025 inches and the vent channel <b>260</b> is approximately 0.040 inches. Were any debris to enter the exit vent <b>270</b> and pass into the vent cavity <b>266</b> (<figref idref="DRAWINGS">FIG. 3</figref>), such debris would have to be small enough to pass between the walls <b>264</b> and the riser interior surface <b>39</b>. Therefore, the walls <b>264</b> and the interior surface <b>39</b> perform a straining function for keeping large particles from reaching the cup vent channel <b>260</b>.

After the water passes through the lower passageway <b>162</b>, it principally flows through the swirl stator <b>170</b>. As stated above, the swirl stator <b>170</b> includes the stator shell <b>172</b> surrounding the stator plate <b>174</b>. The stator shell <b>172</b> is generally cylindrical and sized to be received within and fit closely within the body shell <b>126</b> with close contact between a stator outer surface <b>300</b> and a body shell inner surface <b>302</b>.

As can be seen in <figref idref="DRAWINGS">FIGS. 2</figref>, <b>10</b> and <b>11</b>, the stator outer surface <b>300</b> includes a series of annular prongs <b>304</b> extending radially outward and located proximate to a top edge <b>306</b> of the outer surface <b>300</b>. The body shell <b>126</b> includes mating openings <b>308</b> so that, when the swirl stator <b>170</b> is inserted therein, the prongs <b>304</b> are received within the openings <b>308</b> to secure and position the swirl stator <b>170</b> therein. Once the swirl stator <b>170</b> has been secured within the body <b>122</b>, the PR module <b>20</b> may be installed in the riser <b>30</b> and secured therein by an annular upper barb <b>310</b> located along a top edge <b>312</b> of the body shell <b>126</b>, the upper barb <b>310</b> making an interference fit with a groove <b>314</b> on the interior surface <b>39</b> of the riser <b>30</b>.

The stator plate <b>174</b> generally extends transversely across the interior of the stator shell <b>172</b>. As noted herein, a bottom side <b>320</b> of the stator plate <b>174</b> includes the shoulder <b>178</b> for abutting the top of the valve seat member <b>182</b>. Above the shoulder <b>178</b>, the stator plate <b>174</b> and shell <b>172</b> are joined by a contoured arcuate surface <b>322</b> (<figref idref="DRAWINGS">FIG. 3</figref>) sloping upward and inwardly toward the axis X. This arcuate surface <b>322</b> smoothes the path of the water through the lower passageway <b>162</b>, thereby reducing head loss.

Positioned on the bottom side <b>320</b> in a radial manner are flow openings <b>324</b> for allowing water to pass through the plate <b>174</b>. In the preferred embodiment, there are three such openings <b>324</b>, and edges <b>326</b> thereof may be rounded to reduce head loss and ease the flow of water therethrough. Each opening <b>324</b> passes from the bottom side <b>320</b> to a top side <b>328</b> for delivering water from the lower passageway <b>162</b> to the intermediate passageway <b>74</b> and the turbine <b>72</b>. Surrounding each opening <b>324</b> on the top side <b>328</b> is a swirl director <b>330</b> for directing the water into the turbine <b>74</b>. More specifically, the swirl director <b>330</b> includes an opening <b>332</b> pointed in a direction transverse to the axis X and, preferably, in a direction generally angled upwardly from a line tangential from the axis X. In this manner, the direction of the water flowing therethrough has an upward component so that the water flows towards the turbine vanes <b>78</b> and, more importantly, has a spiral flow path so that it provides a horizontal force component. The preferred vanes are generally vertical, and thus, the spiral flow and horizontal force component supplies the force used to rotate the turbine <b>74</b> for rotating the sprinkler head, as discussed above. In a preferred form, the swirl direct <b>330</b> and opening <b>332</b> produces a discrete stream or jet of water or fluid directed toward the vanes <b>78</b>.

The swirl stator <b>170</b> further includes radial ribs <b>334</b> extending vertically downward from the plate bottom side <b>320</b>. In the preferred embodiment, three radial ribs <b>334</b> are provided, each located between bottom side openings <b>324</b>. When the swirl stator <b>170</b> is installed in the body <b>122</b>, the ribs <b>334</b> contact the upper flange <b>234</b> of the moveable member <b>200</b> and force the moveable member <b>200</b> downward to compress the moveable member spring <b>202</b>. Each rib <b>334</b> has an axial extension <b>336</b> located on a bottom edge <b>338</b> thereof, the axial extension <b>336</b> being positioned a short distance radially outboard from where the upper flange <b>234</b> contacts the rib <b>334</b>. The axial extensions <b>336</b> serve to help maintain the moveable member <b>200</b> in proper vertical and axial alignment.

The vertical dimension of the ribs <b>334</b> provides a spacing between the moveable member <b>200</b> and the stator plate <b>174</b>. In fact, fluid is generally free to flow through the volume between the moveable member <b>200</b> and the stator plate <b>174</b>, and the pressure therebetween is equal to the pressure in an upper portion <b>162</b><i>a </i>of the lower passageway <b>162</b> (<figref idref="DRAWINGS">FIG. 3</figref>). Located above the moveable member <b>200</b> in the center of the stator plate <b>174</b> and axially aligned therewith is the bypass valve assembly <b>350</b>.

The bypass valve assembly <b>350</b> acts to maintain a relatively constant rotation speed for the head <b>60</b>, independent of the flow rate of the nozzle <b>52</b>. Broadly speaking, the assembly <b>350</b> remains closed when a force differential applied to the assembly <b>350</b> remains lower than a specific threshold. More specifically, a portion of the assembly <b>350</b> is exposed to the pressure within the lower passageway <b>162</b> while another portion of the assembly <b>350</b> is exposed to the pressure within the intermediate passageway <b>74</b>. As pressure on an area produces a force, the respective pressures act upon the portions to apply generally counterposed forces. When a differential between these forces that exceeds the threshold is applied, the assembly <b>350</b> is forced open, thereby allowing water to pass through the swirl stator <b>170</b> without passing through the swirl directors <b>330</b>. Water passing through the assembly <b>350</b> has a generally vertical direction of flow and, thus, does not tend to apply a rotational force to the vertically positioned vanes <b>78</b> on the turbine <b>72</b>. In fact, the vertical flow of water through the vanes <b>78</b> and in the intermediate passageway <b>74</b> may retard the motion of the turbine <b>72</b>, thereby reducing the likelihood that the rotational velocity of the turbine <b>72</b> will become excessive. The assembly <b>350</b> is biased to the closed position by a bypass spring <b>352</b> such that the force differential created by the water pressures in the lower and intermediate passageways <b>162</b>, <b>74</b> must overcome the bias force provided by the bypass spring <b>352</b> to open the assembly <b>350</b>.

With reference to <figref idref="DRAWINGS">FIGS. 10 and 11</figref>, the bypass valve assembly <b>350</b> includes a circular bypass opening <b>354</b> concentrically formed in the center of the stator plate <b>174</b> and passing from the plate bottom side <b>320</b> and through the plate top side <b>328</b>. The bypass opening <b>354</b> is in fluid communication with the volume above the moveable member <b>200</b> and, accordingly, with the lower passageway <b>162</b>. Edges <b>356</b> of the bypass opening <b>354</b> on the bottom side <b>320</b> are rounded to reduce head loss through the opening <b>354</b>. The radial ribs <b>334</b> are joined at a hub <b>358</b> having a central bore <b>360</b> coaxially aligned with the axis X such that the hub <b>358</b> is positioned below the bypass opening <b>354</b>.

As can be seen in <figref idref="DRAWINGS">FIGS. 8 and 9</figref>, the bypass valve assembly <b>350</b> utilizes a reciprocating valve member <b>362</b> for opening and closing the assembly <b>350</b>. The valve member <b>362</b> includes a circular valve plate <b>364</b> with a diameter greater than the diameter of the bypass opening <b>354</b>. The valve member <b>362</b> is positioned above the bypass opening <b>354</b> so that a bottom side <b>366</b> of the valve member <b>362</b> rests on the plate top side <b>328</b> when the assembly <b>350</b> is closed, thereby preventing the flow of water through the bypass opening <b>354</b>. Conversely, when force applied to the valve member <b>362</b> by the pressure in the lower passageway <b>162</b> is sufficiently greater than force applied by the pressure in the intermediate passageway <b>74</b> to exceed the threshold level, the valve member <b>362</b> is forced upward, thereby separating the valve plate <b>364</b> from the stator plate top side <b>328</b>. As such, water is able to flow through the bypass opening <b>354</b>, thus reducing the pressure within the upper portion <b>162</b><i>a </i>of the lower passageway <b>162</b>. As discussed above, the water flowing through the bypass opening <b>354</b> does not contribute to rotating the turbine <b>72</b>.

The valve member <b>362</b> further includes a central post <b>370</b> depending downward from the valve plate <b>364</b> and a spring retainer <b>372</b> secured to the bottom of the central post <b>370</b>. The post <b>370</b> is located within the hub <b>358</b> and is shiftable up and down therewithin as the valve assembly <b>350</b> is opened and closed. The bypass spring <b>352</b> is positioned between the ribs <b>334</b> and the spring retainer <b>372</b> for biasing the spring retainer <b>372</b> downward away from the ribs <b>334</b>.

More specifically, the bypass spring <b>352</b> is a coil spring having a top edge or coil <b>376</b> in contact with lower edge <b>338</b> of the ribs <b>334</b> and a bottom edge or coil <b>378</b> in contact with the spring retainer <b>372</b>. Accordingly, a portion of the bypass spring <b>352</b> is positioned around the hub <b>358</b>. In order for the assembly <b>350</b> to open, the valve plate <b>364</b> shifts upward, as do the post <b>370</b> and the spring retainer <b>372</b>. In order for the valve member <b>362</b> to shift upward, the force differential across the valve member <b>362</b> must exceed the spring force of the bypass spring <b>352</b> to compress the bypass spring <b>352</b> between the spring retainer <b>372</b> and the ribs <b>334</b>.

With reference to <figref idref="DRAWINGS">FIG. 12</figref>, the spring retainer <b>372</b> includes a bore <b>380</b> for receiving the central post <b>370</b> therein during assembly. Preferably, the post <b>370</b> and spring retainer <b>372</b> are permanently affixed together once assembled. The spring retainer <b>372</b> generally has a hub <b>382</b> defining the bore <b>380</b> and radial spokes <b>384</b> extending from the hub portion <b>382</b>. The spokes <b>384</b> include terminal foot portions <b>386</b> having a reduced height so as to form a horizontal shoulder <b>388</b> and a vertical shoulder <b>390</b> thereon. The bottom coil <b>378</b> of the bypass spring <b>352</b> is positioned on top of the horizontal shoulder <b>388</b> while the vertical shoulder <b>390</b> is positioned within the bypass spring <b>352</b> so as to maintain the spring <b>352</b> in proper axial alignment. Between adjacent spokes <b>384</b> are gaps <b>392</b> so that particulate matter or debris that may be received within the spring <b>352</b> simply pass through and fall out of the bypass valve assembly <b>350</b>.

The moveable member <b>200</b> has an upper cavity <b>400</b>. As fluid flows above the moveable member <b>200</b>, particulate matter therein may fall into the moveable member <b>200</b> so that the upper cavity <b>400</b> collects the debris so that the debris does not pass into the turbine or through other moving parts where the debris may cause binding or excessive wear.

The moveable member upper cavity <b>400</b> also provides the PR module <b>20</b> with a compact design. As can be seen, portions of the bypass assembly <b>350</b> reside in the upper cavity <b>400</b>, particularly the central post <b>370</b> and the spring retainer <b>372</b>.

As water enters the sprinkler <b>10</b>, the riser <b>30</b> is forced to an extended position, and the exit vent <b>270</b> is exposed to the environment, as is depicted in <figref idref="DRAWINGS">FIG. 1</figref>. The water flows through the screen <b>98</b>, enters the PR module <b>20</b> through the openings <b>160</b> in the body <b>122</b>, and flows into the lower passageway <b>162</b>. The water flows upward through the lower passageway <b>162</b> to the stator plate <b>174</b> and through the bottom side flow openings <b>324</b>. The swirl directors <b>330</b> direct the water exiting the openings <b>324</b> into the turbine vanes <b>78</b> for driving the turbine <b>72</b> and drive train <b>82</b> and, thus, the sprinkler head <b>60</b>. Particulate matter that is able to pass through the screen may be deposited in the upper cavity <b>400</b> of the moveable member <b>200</b>. After passing through the turbine <b>72</b>, the water flows through the upper passageway <b>90</b> for delivery to the sprinkler head <b>60</b> for emission in a radial manner.

If greater than a predetermined threshold, a force differential across the valve member <b>362</b> is sufficient to overcome the bias of the bypass spring <b>352</b>, and the bypass valve assembly <b>350</b> shifts upward. This shift allows a portion of the water to flow through the bypass opening <b>354</b> in the stator plate <b>174</b>. This flow will not be directed against the vanes <b>78</b> with a spiral flow horizontal force component. Thus, the rotational velocities of the turbine <b>72</b> and the sprinkler head <b>60</b> are controlled. Additionally, opening of the bypass valve assembly <b>350</b> reduces the pressure within the PR module <b>20</b>. The predetermined threshold for opening the bypass valve assembly <b>350</b> is generally based on the spring constant of the bypass spring <b>352</b> and the pressure within the intermediate passageway <b>74</b>, each of which depends on the sprinkler in which the PR module <b>20</b> is utilized.

The moveable member spring <b>202</b> has a spring constant greater than that of the bypass spring <b>352</b>, and thus requires a greater force to compress. If the pressure in the lower passageway <b>162</b> is sufficient to compress the moveable member spring <b>202</b>, the moveable member <b>200</b> will be forced downward. This causes the flow portion <b>222</b> of the moveable member <b>200</b> to move closer to the valve surface <b>194</b> of the valve seat member <b>182</b>, thus narrowing the lower passageway <b>162</b> therebetween. In this manner, the flow rate through and the pressure within the lower passageway <b>162</b> in the region above the valve surface <b>194</b> are decreased. Accordingly, the force of the water passing through the swirl directors <b>330</b> and against the turbine vanes <b>78</b> is controlled as to be within the desired range. As the moveable member <b>200</b> is forced downward, the vent channel <b>260</b> from the cup <b>124</b> allows air or fluid to pass into the vent cavity <b>266</b> from where it may exit through the exit vent <b>270</b> to the environment.

According to the described sprinkler <b>10</b>, the PR module <b>20</b> may be provided as a single unit for controlling the pressure and flow rate of water through the sprinkler, as well as the rotational velocity of the sprinkler head <b>60</b>. The PR module <b>20</b> has a compact design including the bypass valve assembly <b>350</b> and the pressure regulating valve assembly <b>180</b> for regulating pressure and flow. As such, the bypass valve assembly <b>350</b> and pressure regulating valve assembly <b>180</b> are nested, such that the former is embedded within the latter. The compact size allows the PR module <b>20</b> to be retrofitted in sprinklers, though in some cases removing of an existing pressure regulator, bypass valve, or stator plate may be necessary. In addition, the compact size allows the PR module <b>20</b> to be included in sprinkler types that previously were considered too small to accommodate both a bypass valve and a pressure regulator. In fact, the PR module <b>20</b> may be included in a sprinkler below a drive mechanism, as has been described herein, for rotating a sprinkler head, as well as a direction-changing trip-mechanism <b>402</b> for reversing the direction of the sprinkler.

While the invention has been described with respect to specific examples, including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above-described systems and techniques that fall within the spirit and scope of the invention as set forth in the appended claims.